Reinforcing-bar for concrete constructions.



J. M. DUDLEY. REINFORCING BAR FOR CONCRETE UONSTRUUTIONS. APPLICATION FILED AUG. 5,1907.

928,430, 7 Patented July 20,1909:

PATENT OFFICE.

JAMESM. DUDLEY, OF BESSEMER, ALABAMA.

REINFORCING BAR; FORJ GONGRE TE CON STRUG TIONS.

Specification of Letters Patent.

Application filed Augusto, 1907-. Serial No. sauce.

To all whom itmay concern:

Be it known that l, JAMES M. DUDLEY, a citizen of the United States, residing at Bessemer, inthecounty' of J efferson-and State of Alabama, have invented new and useful Improvements in Reinforcing- Bars for C011- crete Constructions, of which the following is a specification.

My invention relates to metalbars. or rods for reinforcing concrete or similar constructrons.

It is my object to produce a reinforcing bar which shall, as a whole, possess the maximum strength for its weight in metal and which shall be so desi ned that it may be readily and cheaply rolled into the desired conformation which will be such as toform a rigid mechanical bond with fnaterial in which it is embedded.

' indenting only its corner edges, W

With the above obi'ects' in view I use: a bar of metal which is poh'ygonal in cross section and has its edges 0 y indented in such a manner as to give thebar a substantiallv uniform cross-sectional area which shall be but little less than the cross-sectional area of the original stock, the indentations being such as to give the desired gripping surfaces Without.

appreciably weakenin' the bar and as to be readily formed by rofiing so that the bars ma be produced at aminimuin cost. By ut' izing a rectangular bar, as I refer, and

ldile leaving the main side faces of the bar undisturbed, l secure a bar which is subjected to the minimum strain in manufacture and has no cross cuts or indentations across or inits side faces which wouldgreatly weaken the bar as a whole. As a result of my construction the bar Will have a tensile strength er unit of cross-sectional area equal to that of the original stock and at l e same time will have nearly an equal cross-sectional area with the original stock.

Referring to the accompanying drawings in which I have illustrated preferred formsof my invention:-Figure 1, represents an elevation of a square bar looking at it from one of its indented edges. Fig. 2, represents a cross-sectional view along the line :cm, Fig.

L Fig. 3, represents aplan view looking at one side of the bar which may be either square or rectangular. Fig. 4, represents a view of ,a narrow side of a flat rectangular bar. Similar reference characters refer to similar parts throughout the drawings.

Referring to the bar illustrated in Fig. 1,

this is formed from square stock which is provided along each. of its four edges With a serles of spaced indentations. 1 which are illustrated asnotches having slanting grip-- ping faces 2 and straight longitfidinal faces 3 forming the bottom of the notches. notches are diametrically oppositely disposed in pairs and arranged so that the grip;- ping faces 2 on the'notches along one pair of diametrically opposite edges overlap in transverse planes the reversely disposed gripping faces of the notches in the other pair of diametrically opposite edges. In other words, the notches are arranged in oposite airs which are staggered relatively.

t will e noted in Fig.-

that the adjacentside' edges 2 and 2 of the gripping faces 2 in any side face of the bar are parallel, the

several gripping faces having the same angular inclination. This arrangement of the notches produces a bar which will have, the.

same cross-sectional area at the points of intersection by the planes (1., b andc of Fig. 1, and'therefore throughout its whole length. The planes a, b and 0 will intersect the bar so as to form polygons, whose areas will be equal. a

In Fig. 3 it Will benoted that the ortions of the side ,faces of the bar included etwecn the lines d and d are left entirely unaffected by the operation of forming the notches, thereby leaving undisturbed the major por-- tion of the bar, such as is included in the hexagonal area which in Fig. 2 is bounded by the full and dotted lines and the ortions of the sides between the lines (1 and This longitudinal hexagonal central portion of the Patented. July 20, r909;

The-

bar being unweakened by the process of forming the notches or gripping indentations would therefore possess per unit of cross-sectional area the full tensile strength of the original stock which it ract'ically equals in cross-sectional area. rolled in the edges :with ap roximately one third of the power that won (1 be required to roll similar notches extending across the side faces of the stock or dl'sposed wholly within a side face.

While this construction illustrated is preferable for producing an absolute uniformity of cross-sectional area throughout the-fb'ar, the same results may be practically obtained where curved or V-shaped notches are similarly disposed in the same staggered manner along the edges so as to ,produce substantial uniformity in cross-sectional area.

'l e notches may be In Fig. 4 I have illustrated a flat rectangular bar, the wide side faces of which correspond to the showing in Fig. 3.

Obviously my improved bar may be formed in various sha es from different kinds of stock, the lengt and depth of the indentations being designed as occasion may require. Also the form and design of the bar may be variously modified within the scope of my invention.

Having heretofore illustrated and described several preferred forms of my inven tion I desire, without particular limitation thereto, to secure and protect by Letters Patent, the following.

A reinforcing bar of substantially rectangular cross section with two of the oppositely disposed corners having alternate angled and flattened sections and the remaining two corners similarly constructed, the flattened portions of each pair of corners being adjacent the angled portions of the remaining pair of corners, each'of the flattened portions terminating in triangular )lane surfaces the apexes of which lie in the lines of the angled portions and the bases in the planes of the'flattened portions, the triangles of one pair of corners lying adjacent the triangles of the other pair and reversely directed.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

JAMES M. DUDLEY. 

